from wtforms import DateTimeField, SelectMultipleField, SelectField
from wtforms.widgets import html_params, HTMLString, ListWidget, CheckboxInput
from wtforms.validators import StopValidation
import pytz
from datetime import datetime
from flask_babelex import to_user_timezone, gettext
from project.dateutils import berlin_tz

class MultiCheckboxField(SelectMultipleField):
    widget = ListWidget(prefix_label=False)
    option_widget = CheckboxInput()

def create_option_string(count, value):
    result = ""
    for i in range(count):
        selected = " selected" if i == value else ""
        result = result + '<option value="%02d"%s>%02d</option>' % (i, selected, i)
    return result

class CustomDateTimeWidget:
    def __call__(self, field, **kwargs):
        id = kwargs.pop('id', field.id)
        date = ''
        hour = minute = 0
        if field.data:
            date_value = to_user_timezone(field.data)
            date = date_value.strftime("%Y-%m-%d")
            hour = date_value.hour
            minute = date_value.minute

        date_params = html_params(name=field.name, id=id, value=date, required=field.flags.required, **kwargs)
        time_hour_params = html_params(name=field.name, id=id + '-hour', **kwargs)
        time_minute_params = html_params(name=field.name, id=id + '-minute', **kwargs)
        clear_button_id = id + '-clear-button'

        return HTMLString('<div class="input-group-prepend mt-1"><input type="text" class="datepicker" {}/><button class="btn btn-outline-secondary" type="button" id="{}"><i class="fa fa-times"></i></button></div><div class="mx-2"></div><div class="input-group-append mt-1"><select {}>{}</select><span class="input-group-text">:</span><select {}>{}</select></div>'.format(date_params, clear_button_id, time_hour_params, create_option_string(24, hour), time_minute_params, create_option_string(60, minute)))

class CustomDateTimeField(DateTimeField):
    widget = CustomDateTimeWidget()

    def process_formdata(self, valuelist):
        if valuelist:
            try:
                date_str, hour_str, minute_str = valuelist
                if not date_str:
                    self.data = None
                    return

                date = datetime.strptime(date_str, "%Y-%m-%d")
                date_time = datetime(date.year, date.month, date.day, int(hour_str), int(minute_str))
                self.data = berlin_tz.localize(date_time)
            except:
                raise ValueError('Not a valid datetime value. Looking for YYYY-MM-DD HH:mm.')

class CustomDateWidget:
    def __call__(self, field, **kwargs):
        id = kwargs.pop('id', field.id)
        date = ''
        if field.data:
            date_value = to_user_timezone(field.data)
            date = date_value.strftime("%Y-%m-%d")

        date_params = html_params(name=field.name, id=id, value=date, **kwargs)
        return HTMLString('<input type="text" {}/>'.format(date_params))

class CustomDateField(DateTimeField):
    widget = CustomDateWidget()

    def process_formdata(self, valuelist):
        if valuelist:
            try:
                date_str = valuelist[0]
                if not date_str:
                    self.data = None
                    return

                date = datetime.strptime(date_str, "%Y-%m-%d")
                self.data = berlin_tz.localize(date)
            except:
                raise ValueError('Not a valid date value. Looking for YYYY-MM-DD.')

def try_to_int(value):
    if isinstance(value, int):
        return value

    if isinstance(value, str) and value.isdigit():
        try:
            return int(value)
        except ValueError:
            return value

    return value

class TagSelectField(SelectField):

    def __init__(self, label=None, validators=None, coerce=try_to_int, choices=None, validate_choice=True, **kwargs):
        super(TagSelectField, self).__init__(label, validators, coerce, choices, validate_choice, **kwargs)

    def pre_validate(self, form):
        if self.is_free_text():
            if not self.data or not self.data.strip():
                raise StopValidation(gettext('This field is required'))
        else:
            super(TagSelectField, self).pre_validate(form)

    def is_free_text(self):
        return isinstance(self.data, str)